Beana's Para Siempre review: Dining room decorations are a big part of the charm at Beana's in Rahway.

Ed Murray/The Star-Ledger
Shrimp, onions and peppers can be wrapped in tortillas to make shrimp fajitas at Beana's Para Siempre in Rahway.

The trouble with Mexican food is the Americanization of it. We expect gargantuan portions — mightily cheesy ones at that, at impossibly cheap prices. Plus margaritas.

Our introduction to Mexican food doesn’t hail from its homeland. It comes from school cafeteria tacos and chain food distortions. Just add hot sauce.

It’s no wonder, then, that most of us don’t understand the subtle and mystical qualities of Mexican food — the powerful undercurrents of a cuisine so vividly illuminated in movies such as “Like Water for Chocolate.” Or, for a more modern theatrical reference, in the movie “Frida,” as we witness the power of mole — how it brings together the wife and the ex-wife of Diego Rivera.

Where, we wonder, is that Mexican cuisine?

U.S. Census figures show a dramatic increase in the number of Mexican immigrants in New Jersey; the number is up 115,000 since 2000. That’s good news for those hoping for more authentic Mexican cuisine. Good news, too, for those wishing to spot more than the occasional white-fleshed guava in our supermarkets (guayabas en sancocho, anyone?)

Still, we often have to suffer through cheap and cheesy imitations, hoping for breakthrough moments of authenticity, complexity and subtlety here and there as they come.

A few of those moments come at Beana’s in Rahway, a somewhat recent addition to the culinary scene.

You’d shriek if you stumbled onto this restaurant along a dusty stretch of Route 66, pulling out your camera to document your touristy luck to your disbelieving friends. The place is thoroughly fun and kitschy, its walls crammed with 70-year-old license plates, sombreros, commemorative dishware, velvet paintings of bullfights and countless crosses, lizards and chili pepper lights.

Try the chorizo appetizers ($7.95), crisp, like skinny french fries, served with a jalepeño-spiked pico di gallo and sour cream; the chicken enchilada ($13.95), with its swirl of rich mole sauce; the flaky empanadas ($8.95), with their surprise of a few musky olives inside; the unexpectedly light pulled-pork quesadilla ($13.95), with its caramelized leeks; the silky homemade flan ($6.95).

Even a dish that doesn’t work — the Tequila Sunrise chicken ($18.95), with its chicken too dry and tough and its orange sauce too sweet and syrupy to consume for long, gets points for trying. Yes, the portions are still gargantuan (it is America, after all). And the standbys such as the chicken taco ($13.95) and the beef burrito ($13.95) — along with their accompanying beans (black, red or refried) and rice — are just what you’d expect to find in any other Mexican restaurant.

The kitchen is too cozy with salt, even for those who consider salt a friend. The salsa disappoints, and service is inconsistent. And no, you can’t order a margarita.

But Beana’s is fun, and perhaps offers a taste of what’s to come: an ever-evolving mashup of Mexican and American, even if that means the quite unexpected — in this case, a not-so-bad version of homemade pumpkin pie ice cream ($5.95) — along the way.